Help on Ph Acid/Base science Fair experiment

[-Demosthenes-]

I'm doing a science fair experiment for highschool.

I'm testing for natural acid/base indicaters.

I'm using Lemon juice for acid, Ammonia for Base, and distilled water for nurtrol.

I'm testing all kinds of vegatable and fruit juice to see if they cange color in the Acid/Base solution.

Do you have any suggestions (Of course I'm going to use cabbage juice) They would help me alot! I really respect you all, especially your college degrees, and I will very much appreciate your help and suggestions!

 

PS- Most of my Chem grade rides on this Science fair

[YT2095]

"I'm testing for natural acid/base indicaters"

 

if you have an Indian shop local to you, buy some powdered Turmeric, it`s bright yellow in color, but turs red with Alkaline materials

 

the liquid from Red Cabbage is also used as an indicator, although I forget which way around that works (it`s been a long time).

[wolfson]

Ok so you need to explain what pH is first of all, if you want me to I will.

Second you need to show the reader(s), how pH colour(s) increase/decrease according to concentraion (Molarity), you also need to include the water constant (kw) and its uses in calculating pH of bases, and of course show how to calculate the pH of an acid.

[YT2095]

also if you wish to use ALL natural products, Ammonia would be difficult to produce unless you had alot of time (urea breakdown produces it).

why not try Wood Ash

Potassium Hydroxide and carbonate (both are very alkaline) and it`s also very easy to make!

burn a pile of wood untill you`re left with the grey ash (not the black charcoal bits), put it in a jar, add some boiling water to just cover the ash level, give it a good stir, the pour the mix through a coffee filter paper, the clear liquid will be very alkaline!

[-Demosthenes-]

Ammonia is what I'm using to test as a base. I just need a base to test the juices in, to see if the Juices change color. I'm testing the juices, they are pretty much natural.

[YT2095]

fine, and yes Ammonia is indeed a base, but I thought you were after all "natural" products" and wood ask extract is a stronger base than Ammonia

[-Demosthenes-]

I need my ph balace indicaters to be natural, I could care less if the Acids or bases are, as long as I can test my natural ph balance indicaters in them.

Do you know a stronger acid than Lemon juice? or base stronger than Ammonia? that's easy enough to get, you know from like wal-mart?

[YT2095]

wood ash is strong base!

as for acids, Muriatic acid (often sold as path cleaner) is a very strong acid it`s Hydrochloric, it`ll kick ass out of citric from lemon juice

 

you could bye some "red Devil" drain cleaner otherwise known as Lye, it`s Sodium Hydroxide) a very strong base also, it`s quite pure too!

 

please be carefull with materials though, each is more than cappable of blinding you or taking your skin off. they`re at the Extreme levels of Acid and Base.

don`t use mineral water for your neutral, it contains Ions.

goto a local garage and buy a bottle of top-up water for car batteries, it`s PH is neutral and it contains little to no Ions

[-Demosthenes-]

Thanks! I will be carefull! Any other suggestions for my experiment? They will be very appreciated!!

[-Demosthenes-]

What kind of Juices are most likely to change color in the Acid/Base solutions?

I'll be back in a little while, and I'll check! Thank you so much!

[YT2095]

seriously man, get some turmeric, it`s great!

it`s the same stuff used to color curries and certain meats, it`s a root originaly thats peeled, then dried, then ground into a very fine yellow powder, makes an excellent Base detector, just don`t get it on your clothes, the stains are a b!tch to get out!

[-Demosthenes-]

Is it hard to get?

What about the juices? what kinds should I use?

Thank you!

[Sayonara]

You can get turmeric in your supermarket if there isn't an international food store near you.

 

It'll be in the seasonings or herbs & spices section, or the Indian Cuisine section if there is one.

 

YT's the man for this kind of experiment

[-Demosthenes-]

Thank you.

Do I sprinkle the powder into the Acid/Base solutions to see the color change?

[-Demosthenes-]

I'll check back in an hour, I really will this time! Thank you so much!

[wolfson]

-Demosthenes- welcome to the Science Forums, are you titrating?

[-Demosthenes-]

What's Titrating?

I looked on encarta and it said that it meant, to find the concetration of a solution.

[YT2095]

ok, in practical terms, it means that you have a solution that is maybe Base or Acid (makes no difference really). then you add an indicator to this soln, then slowly you add the opposite to that acid or base a tiny bit at a time until the indicator chages color, but you KNOW the strength of the soln (opposite) that you added, and so from there you can calculate from the amount you had to add to create a change, the strength of the original soln you were adding it to

 

I`ve put this in very simple terms and applied it to PH only, there is alot more to titration than just that, but in effect, that`s what he`s asking I beleive

[-Demosthenes-]

I'm just putting the Juice on a paper towel and letting it dry, and then using it like...uh... limthus paper, I think it is.

[-Demosthenes-]

But how will I use the Tumeric powder ??? Just add it to the acid solution, and see the change in color?

[YT2095]

you may use turmeric in the same way as your cabbage juice, get a glass of warm water add a few spoonfulls of the turmeric, stir well, and then soak your paper in it and let it dry

it tests for Base, it remains yellow with acid.

[-Demosthenes-]

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